The "z" library implements the commonly required image processing
basics of scaling, colorspace conversion, and depth conversion. A
simple API enables conversion between any supported formats to operate
with minimal knowledge from the programmer. All library routines were
designed from the ground-up with flexibility, thread-safety, and
correctness as first priorities. Allocation, buffering, and I/O are
cleanly separated from processing, allowing the programmer to adapt
"z" to many scenarios.

WWW: https://github.com/sekrit-twc/zimg